You can hit this keystroke to do a screen capture, , Shift, 3. You can then upload that picture so we can all see it. Are just the words/letters themselves that are messed up? Are any graphics/pictures distorted too? If so then it's more then likely that the system is corrupted somehow. Try reinstalling the original software again. Make sure you backup all your information first though.

Like others said, it could also just be your video card or logic board. Does it happen after a while. It's probably getting too hot and that's why you are getting the distortions. I'd recommend cleaning out all the dust in your system and removing the graphics card and dusting that too.

Yeah, bad video card... if it's not covered under the recall, you'll need to get a new one and really that's not to big a deal as a video can be had for cheap these days. Just make sure you get a mac card or one that can be flashed for OS X.

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